States' laws could cause complications for same-sex couples

Minnesota becomes the 12th state in the nation where same-sex marriage is legal starting at midnight.

A law approved by state legislators in May extends state benefits to same-sex couples who marry that previously were available only to married couples of the opposite sex. The benefits range from hospital visitation rights to the ability to file joint tax returns.

But life for couples who are married in states like Minnesota, but work or seek medical treatment in states that do not recognize same-sex marriage will be complicated, University of Minnesota law professor Dale Carpenter said.

"There are already many lawsuits that have been filed that deal with some of these issues," Carpenter said. "I think we're going to see those sorts of things worked out in litigation over the next few years."

But Carpenter said gay and lesbian couples who already were validly married in other states will have their marriages legally recognized in Minnesota once the law goes into effect.